Recently updated data show that at least 159 cases of measles have been confi rmed in the United States of America in 2019, that is in fact an unwelcome resurgence of viral infection, which had been eliminated in 2000. Alexander said “ Charlants and internet fraudsters who claim that vaccines aren’ t safe are preying on unfounded fears and daily struggles of parents, and they are creating a public health hazard that is entirely preventable” (1).

INTRODUCTION: Theophylline has different interactions with calcium antagonists. Significant interactions between theophylline and diltiazem and to a lesser degree verapamil have been demonstrated, however, no data are available on the interaction between theophylline and nifedipine. This study was conducted to investigate the effect of nifedipine therapy on theophylline pharmacokinetics.METHODS: In order to investigate the effects of nifedipine on the pharmacokinetics of theophylline, intravenous aminophylline (400 mg) was administered to six healthy male nonsmokers prior to, and following 12 days of oral nifedipine therapy (30 mg/day). Liver and kidney function tests were performed to exclude subjects with hepatic or renal dysfunction. In addition, subjects receiving medications that could influence hepatic function or those known to inhibit or stimulate theophylline metabolism were excluded.RESULTS: Theophylline half-life increased significantly (36%)whereas total body clearance showed a significant decrease following nifedipine therapy (23%). Theophylline volume of distribution was changed.DISCUSSION: Inhibition of theophylline metabolism by nifedipine can partly explain significant changes in theophylline pharmacokinetics. A clinically important

Let [A] = [[aij]] n×n be an interval for [aij] = [-aij, `aij] (i, j=1, 2,..., n). In transformation a matrix into upper triangular matrix by Gauss method, entries under the main diameter should be zero by elementary row operations. In this paper we consider zero as an interval, and, we would apply Gauss ELIMINATION method on interval matrix by arithmetic operations on intervals and the definition of comparison method interval dates, we would use Gauss ELIMINATION method on interval matrix.